This invention relates to a manipulator device for a reflecting mirror such as one for use in laser surgical operations, and more particularly to a device for adjusting the reflecting mirror thereof.
FIG. 1 shows an example of a joint portion of a conventional manipulator device. As shown in the figure the device provides an incident beam axis 1 which is the center of an incident beam stream and an outgoing beam axis 2 which is the center of a reflecting beam stream, and comprises a housing 3, an opening 4 in which is mounted a reflecting mirror 8, an arm 5 on which one of end of the housing 3 is rotatably supported through a bearing 6, a mirror holder 7 having one face of which the reflecting mirror 8 is attached, a bolt 9 which acts to press the mirror holder 7 against the housing 3, another bolt 10 which acts to pull the mirror holder 7 apart from the housing 3, a central axis 11 of the opening 4 which substantially bisects the intersection angle between the incident beam axis 1 and the outgoing beam axis 2. Numeral 12 denotes an axis of rotation of the reflecting mirror 8.
Next, the operation of the conventional device having the above construction will be described. In a multi-joint manipulator of the reflecting mirror type, a plurality of joint portions such as that illustrated in FIG. 1 are connected to transmit a laser beam. Therefore, when the incident beam axis 1 is not aligned with the rotation axis 12 of the reflecting mirror 8, a disturbance of the outgoing beam axis 2 increases in proportion to the transmitted distance of a laser beam. As a result, the beam strikes the inside wall of the arm 5 or other part and the laser beam is not transmitted properly. Accordingly, in this joint portion, the incident beam axis 1 and the outgoing beam axis 2 must be adjusted at each jointing portion so as to always align, and a construction which will prevent the non-alignment of the axis due to shocks or other disturbances is required.
To adjust the device as described above, the conventional device illustrated in FIG. 1 is provided with the two types of bolts 9 and 10 mounted at interval of 60 degrees around the mirror holder 7. By properly advancing and retracting the bolts, the adjustment of the slope angle and position of the mirror holder 7 is performed. As a result, the axis of rotation 12 of the reflecting mirror 8 and the incident beam axis 1 are made to align perfectly, and the incident axis 1 and the rotating outgoing beam axis 2 are adjusted so as to perpendicular with each other.
As the joint portion of a conventional multijoint manipulator device for a reflecting mirror is constructed and adjusted as described above, and since the mirror holder 7 is adjusted and secured by the delicate balance of the bolts 9 and 10, the mirror holder 7 can be easily displaced by an external shock. This frequently results in a disturbance of the beam axes. Also, in the conventional construction, the adjustment of the angle and position of the reflecting mirror must be simultaneously performed and both the adjustments relate to each other. Thus, it is difficult to simultaneously adjust the angle and position, and it is impossible to adjust them independently.